1. Field of the Invention
The present invention relates to a semiconductor integrated circuit device, in which data is written to one-time programmable (OTP) memory elements welded by electric current, and a control method therefore.
2. Description of the Related Art
The number of electrical fuse elements used in a system LSI mounted with memory elements is assumed to be several hundred to 1,000. If data is programmed in a plurality of fuses in one write processing cycle, a required current value increases. Thus, a circuit is needed to supply current for programming. Even if programs are simultaneously executed for a plurality of electrical fuse elements, moreover, there are inevitable differences in programming time between the fuse elements.
Thus, the values of currents that flow individually through the electrical fuse elements must be controlled, and this control is laborious. As described in Japanese Patent No. 2007-48394, to overcome this, there is a method in which electrical fuse elements mounted in an LSI are programmed one after another.